This Phase 2 SBIR is for the development of a drug product identified and demonstrated in the Phase 1 SBIR award (R43CA15120-01). The ultimate goal is to produce, sell and deliver doses of high specific activity iobenguane I 131 for radiotherapy in adults and children with neuroendocrine tumors. These are rare tumors with only about 800 cases a year in the US but with poor outcome and no approved effective treatment. The innovation in this proposal is that it uses a solid phase synthetic process to make a proven diagnostic agent in a radio-therapeutic quantity (1 Curie) without the pharmacologically active carrier compound. A type B pre-IND development was held with the FDA where they definitively stated that USP test methods are insufficient to permit human testing of iobenguane I 131 produced by a new method. However, the FDA concluded that literature reports indicate iobenguane I 131 therapy is efficient for treating neuroendocrine tumors and granted Orphan Drug and Fast Tract status for the development of high specific activity drug product. To meet the required quality control of components of the chemistry, manufacturing and controls component of a IND application, the polymer supported drug precursor will be produced according to current good manufacturing practices and analytical tests developed and validated to confirm the identity, purity, performance and impurity profile of the critical component drug precursor. We will also develop a Drug Master File and execute batch records for the production process of the radioactive drug substance. Finally batches of the final drug product will be made and tested for stability and bio-equivalence in transporter expressing cells and in animals. [unreadable] [unreadable] [unreadable]